This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The aim of this project is to study the kidney's ability to eliminate medications. Another aim is to study a drug interaction that occurs in the kidney, using two commonly used medications called PAH and probenecid, and to study how genetics (genes) can predict how well the kidney eliminates medications from the body.